Recently, the installation of energy generation systems (e.g., systems that generate energy using renewable resources such as solar, wind, hydropower, etc.) at residential and non-residential sites has proliferated for various climate, cost, stability, security, and political reasons. One large segment of installed energy generation systems involves solar photovoltaic (PV) systems.
Many installed PV systems can be directly or indirectly connected to utility-maintained electrical grids (e.g., via a site's main panel/main line), and may thus be referred to as “grid-connected” systems. Grid-connected energy generation systems beneficially allow site loads to be serviced in whole or in part from the grid at various times. For example, during evening hours when a PV system cannot generate substantial amounts of energy due to lack of sunlight, a site may draw some or all of its energy from the grid. In some configurations, grid-connected energy generation systems can also allow excess energy generated at the site to be fed back to the grid (and used/stored by others), such as when generated PV energy production may exceed a site's local energy load/use.
However, a limitation with many grid-connected energy generation systems is that, unlike a traditional power plant, the system power output may be intermittent and non-dispatchable. For example, a grid-connected PV system is typically limited in its ability to provide power capacity at times of peak grid loads, balance grid voltage and frequency variability, and/or supply energy when prices are most economic.
To address these and other limitations, some systems have been developed that integrate grid-connected energy generation (e.g., PV) components with an on-site energy storage subsystem, such as a battery device and a battery inverter/charger. In these integrated systems, the energy storage subsystem can be configured to store excess energy as it is generated by the PV components, and possibly dispatch stored energy to satisfy local (or external, grid-wide) loads as needed. Additionally, energy storage capability enables a number of other features that can provide benefits to the site owner or the service provider of the system, such as the ability to “time shift” energy usage to minimize the need to pull energy from the grid, and thus reduce energy costs.
However, energy generation and/or storage systems are largely unable to flexibly adapt to changing conditions specific to the site, nearby sites, region, grid, etc. Accordingly, currently site loads and generators are largely uncontrolled, and at best are operated according to a schedule to provide what is guessed or hoped to be an efficient scheme. However, in reality many use cases would require some sort of additional coordination in real-time between resources—at a site, or perhaps among multiple sites—to actually achieve the desired results. For example, on a cloudy day, energy from a storage system could potentially be dispatched to avoid a demand spike placed upon the grid.
Despite the advantages associated with integrating grid-connected PV energy generation with on-site energy storage, there are a number of challenges that make it difficult to efficiently deploy and control such integrated systems, particularly on a large, distributed scale. For example, it is tremendously difficult to attempt to control large numbers of energy generation and/or storage systems installed at various sites (in various geographic locations) utilizing differing device types that may have different capabilities, differing grid requirements, differing weather conditions, differing energy pricing schemes, etc.
Accordingly, there is a need for efficient, intelligent, adaptive control systems for energy generation and/or storage systems.